Theopedia

Peter Kreeft

“Augustine had the instinct of a sailor: he negotiated the heavy seas of Platonism in the Christian boat without capsizing.”

Peter Kreeft, Socrates’ Children1

Overview

Peter Kreeft (b. 1937) is an American philosopher and Roman Catholic apologist who has taught at Boston College since 1965.2 Raised in the Christian Reformed Church, he converted to Catholicism during his college years and has since written widely on apologetics, ethics, and the history of philosophy, drawing heavily on Thomas Aquinas, Plato, and C. S. Lewis.2 His work on Scripture’s authority and on concupiscence has drawn direct engagement, and correction, from Reformed writers.34

Life and Ministry

Kreeft was born March 16, 1937, in Paterson, New Jersey, to Dutch-American parents and was raised in the Christian Reformed Church.2 He earned a B.A. from Calvin College in 1959, an M.A. from Fordham University in 1961, and a Ph.D. from Fordham in 1965, with a dissertation directed by the Jesuit philosopher W. Norris Clarke, followed by postdoctoral study at Yale.2 During his college years he converted from his family’s Reformed tradition to Roman Catholicism, a decision he traces to investigating the Catholic Church’s claim to be the church historically founded by Christ and applying C. S. Lewis’s “trilemma” reasoning to that claim.2 He joined the philosophy faculty at Boston College in 1965 and has remained there for the whole of his career, also teaching at The King’s College in New York.5

Theological Contribution

Apologetics and the church’s authority over Scripture

With Ronald K. Tacelli, Kreeft co-authored the Handbook of Christian Apologetics (1994), a compendium of arguments for God’s existence and for the truth of Christianity, and he has written Catholic Christianity: A Complete Catechism of Catholic Beliefs Based on the Catechism of the Catholic Church (2001) as a popular-level exposition of Catholic doctrine.5

In Catholic Christianity, Kreeft argues for the church’s authority over Scripture from the fact that the Bible was written by “apostles and saints,” members of the church.6 Michael Kruger answers that this “cause-and-effect” argument confuses the instruments God used to produce the Bible with its ultimate cause: “Although Kreeft is technically correct that the Bible was written by human beings, human beings who were part of the ‘church,’ to say that they are the ‘cause’ of the Bible is obscurant at best… It is God’s activity to inspire the biblical authors that produced the Scriptures. He, not the church, determined what would be inspired and what would not.”3 Kruger argues Kreeft has confused the historical order of church and canon, in which the church came first, with the theological order, in which the canon’s divine origin is prior to the church that received it.3

Concupiscence and moral responsibility

Kreeft’s Catholic Christianity also states the Catholic catechism’s distinction between concupiscence, an inclination toward sin that is not itself culpable, and coveting, a deliberate act of the will that is: “Coveting is to be distinguished from concupiscence, which is not our free choice but our condition… ‘Concupiscence stems from the disobedience of the first sin. It unsettles man’s moral faculties and, without being in itself an offense, inclines man to commit sins’ (CCC 2515). No one can avoid concupiscence. But we can avoid obeying it and being dominated by it.”7 He applies the same distinction to homosexual desire specifically: “It is also necessary to make a clear distinction between homosexual desires, or a homosexual orientation, and homosexual acts. We are responsible for the acts we choose to perform, but not for the desires we experience… Homosexual desires are disordered, but they are not sins.”8

Jared Heath Moore’s dissertation on concupiscence takes Kreeft as its representative voice for this Roman Catholic position and contrasts it with Augustine’s own teaching, which held desire itself, prior to any act of will, to be culpable sin.9 Moore notes that Kreeft “clearly emphasizes that homosexual acts are sin,” but that Kreeft’s case for it appeals to the authority of the church rather than to Scripture directly, and that on concupiscence itself Kreeft follows the Council of Trent’s rejection of Augustine’s stricter position rather than the Reformed tradition, which followed Augustine.7

History of philosophy

Kreeft’s three-volume Socrates’ Children: The 100 Greatest Philosophers (2015) surveys the history of Western philosophy through short profiles of individual thinkers.1 On Augustine, Kreeft argues that of the major early Christian theologians who engaged Plato, Augustine alone “consistently avoided both the simple rejection of Plato as a heretic and the skewering of Christianity in a Platonic direction so as to become somewhat of a heretic himself.”1 Samuel G. Parkison quotes this assessment approvingly in his own dissertation on divine beauty, alongside Kreeft’s account of Augustine’s cosmology: “This cosmology of things as signs or symbols actually gives the world more importance, not less, as a book is more important than a stone to a wise man.”10

Kreeft’s The Platonic Tradition (1993) develops a similar account of Christian Platonism at greater length. Craig A. Carter, whose own Contemplating God with the Great Tradition argues for a retrieval of the same classical theistic tradition, calls Kreeft’s book’s portrayal of Christian Platonism “remarkably similar” to his own, arrived at independently, and separately recommends Kreeft’s C. S. Lewis for the Third Millennium (1994) as “extremely helpful” on Lewis’s critique of modernity.11

Historical Significance

Kreeft’s apologetic writing has drawn direct responses from Reformed writers on two specific points: Kruger’s correction of his ecclesiological argument for the church’s authority over Scripture, and Moore’s use of him as the representative statement of the Roman Catholic position on concupiscence against which the Reformed, Augustinian position is set.34 His work on the history of philosophy and the retrieval of Christian Platonism, by contrast, has drawn approving use from Reformed scholars.1011

Related Doctrines

References

  1. Peter Kreeft, Socrates’ Children: The 100 Greatest Philosophers, vol. 2, Medieval Philosophers, 3 vols. (South Bend, IN: St. Augustine’s Press, 2015), 2:29, quoted in Samuel G. Parkison, “Irresistible Beauty: Beholding Triune Glory in the Face of Jesus Christ” (PhD diss., Midwestern Baptist Theological Seminary, 2021), chap. 1, 14. ↩ ↩2 ↩3

  2. “Peter Kreeft,” Wikipedia, accessed September 2026; the Theopedia Library holds no dedicated biographical source for Kreeft. ↩ ↩2 ↩3 ↩4 ↩5

  3. Michael J. Kruger, Canon Revisited: Establishing the Origins and Authority of the New Testament Books (Wheaton, IL: Crossway, 2012), chap. 1, “The Church’s Book,” citing Peter Kreeft, Catholic Christianity (San Francisco: Ignatius, 2001), 20. ↩ ↩2 ↩3 ↩4

  4. Jared Heath Moore, “A Biblical and Historical Appraisal of Concupiscence with Special Attention to Same-Sex Attraction” (PhD diss., The Southern Baptist Theological Seminary, 2019), chap. 1, “Introduction,” 13-15. ↩ ↩2

  5. Moore, “A Biblical and Historical Appraisal of Concupiscence,” 13. ↩ ↩2

  6. Kruger, Canon Revisited, chap. 1, citing Kreeft, Catholic Christianity, 20. ↩

  7. Moore, “A Biblical and Historical Appraisal of Concupiscence,” 14, quoting Kreeft, Catholic Christianity, 20. ↩ ↩2

  8. Moore, “A Biblical and Historical Appraisal of Concupiscence,” 14-15, quoting Kreeft, Catholic Christianity, 20. ↩

  9. Moore, “A Biblical and Historical Appraisal of Concupiscence,” 13-14. ↩

  10. Peter Kreeft, Socrates’ Children, vol. 3, 3:33, quoted in Parkison, “Irresistible Beauty,” chap. 1, 15. ↩ ↩2

  11. Craig A. Carter, “Do We Worship the God of the Bible?,” in Contemplating God with the Great Tradition: Recovering Trinitarian Classical Theism (Grand Rapids: Baker Academic, 2021), chap. 9, endnote 43, citing Peter Kreeft, The Platonic Tradition (South Bend, IN: St. Augustine’s Press, 1993), and Kreeft, C. S. Lewis for the Third Millennium: Six Essays on the Abolition of Man (San Francisco: Ignatius, 1994). ↩ ↩2